Impedence and inductance cardiography: comparing cardiovascular function with ambulatory estimates
Year: 2013
Type: dissertation
Abstract: An accurate ambulatory monitoring device which detects hemodynamic values outside of the laboratory setting could help researchers and practitioners alike. The ability to monitor changes occurring in a subject during activities of daily living (ADL), could lead to the detection and treatment of many undiagnosed patients. Non-invasive monitoring of hemodynamic variables have gone through many changes since its inception in 1966, when Kubicek et al developed the first impedance cardiograph for NASA. Since then changes have been made to the formula which detects hemodynamic changes, however, the impedance cardiograph is still considered the gold standard for non-invasive monitoring. The current study assessed the accuracy of an ambulatory monitoring device, the Vivometric LifeShirt, compared to the current gold standard impedance cardiograph (Cardiodynamics, Bio-Z), during pre and post rest conditions. Methods:The volunteer subjects included 14 healthy males recruited from California State University, Northridge. The male participants were between the ages of 19-33 and all provided written informed consent. Pre and post test values were obtained while the Cardiodynamics Bio-Z and Vivometric LifeShirt simultaneously recorded hemodynamic values. Heart rate, stroke volume and cardiac output were then analyzed and recorded.\nResults:There was a very strong correlation to heart rate when comparing pre (Pearson correlation = .988, Sig. 2 tailed = .000) and post rest (Pearson correlation = .990, Sig. 2 tailed = .000) data between the LifeShirt and Bio-Z. Although stroke volume and cardiac output did not show strong correlations, a regression equation was determined for the individual variables when using age and body surface area. Conclusions The LifeShirt had a very strong correlation to the Bio-Z in detecting heart rate and has the potential to be used outside of a laboratory setting. However, due to stroke volume and cardiac output being recorded on different scales no correlation was found between the two devices. Future research should examine how a higher subject number may influence the results and potentially produce an individual regression equation in order to predict actual values from the LifeShirt values.
Author: David J. Kessler
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W349265750